This application relates to a seal shaft for supporting a seal in an air cycle machine and wherein the seal shaft is designed to eliminate variation in distance between seal shaft faces.
Air cycle machines are known and are often utilized in aircraft air supply systems, such as conditioning air for use in an aircraft cabin.
In an air cycle machine, a pair of turbine rotors are driven by pressurized air to, in turn, drive a shaft which drives a compressor and a fan. Air compressed by the compressor and moved by the fan is utilized for various operations on an associated aircraft.
In one type of air cycle machine, a first stage turbine rotor is positioned axially adjacent the compressor rotor. A disk shaped seal is fixed in the housing between the two rotors. A seal shaft rotates with the main shaft and radially inward of this disk seal. In the prior art, the seal shaft has sometimes had variation along axial edges. Even a small variation in the position of the edges on the seal shaft can result in a kinking between the two rotors. That is, if the seal shaft edges are not as desired, there may be a variation in the center of gravity of the rotors creating an imbalance, which can cause vibration.